Luminaire



J. P. FOULDS May 6, 1958 LUMINAIRE 2 Sheets-Sheet 1 Filed May 25, 1953 Inventor: John P Foulds,

- His Attorneg.

J. P. FOULDS May 6, 1958 LUMINAIRE 2 Sheets-Sheet 2 Filed May 25, 1953 Fig.5

Inventor:

John P Foulds,

b5 H's Attorneg.

Patented May 6, ,1

2,833,916 LUMINAIRE John P. Foulds, Lynnfield Center, Mass., assignor to General Electric Company, a corporation of New York Application May 25, 1953, Serial No. 357,231

' a 3 Claims. (01. 240-25 riphery in order to be efiective in'protecting the interior of the luminaire. The problem of how best to support these globes under large temperature extremes without causing them. tocrack due .to differential thermal expension of the globe and its support is a serious one.

It is a principal object of this invention to provide.

improved means forsupporting the. elongated globe of such a luminaire so thatthe differences in thermal expansion and contraction of the globe relative toits sup port and the body portionof the luminaire are accommodated by the manner in which the globe is mounted in its support.

Further objects of my invention will become apparent from a consideration of the particular embodiment thereof illustrated in .the accompanying drawings.

Fig. 1 of these drawings is a side view illustrating in outline my improved luminaire which has been shown mounted on a pole with the, globe and support therefor also shown by dot and dash lines in a dropped position when supported by the hinge atone endthereof.

"Fig. 2 is a longitudinal sectional view of my luminaire showing certain structural features thereof.

.Fi'g. 3 is 'anend view, partially in section, of my luminaire showing additional structural features thereof.

Fig. 4 is av sectional view of Fig. 2 taken along the top edge portion of the globe structure and illustrating the'internal structure thereof as well as the manner of its mounting in its supporting frame and the mounting of its supporting frame in the hood structure of the luminaire.

I Fi g. 5 is a fragmental side sectional view of an 'end portion of the globe showing the prism arrangement therein at its ends.

Fig. .6 is a similar end sectional view illustrating the prism arrangement in these ends.

- Fig. 7 is a detail showing the natures of the prisms employed.

Fig. 8 is an exploded detailed view of the separable hinge structure employed for supporting the globe frame in the-hood of my luminaire; and

Fig. 9 is an end view of the hinge arrangement shown in Fig. 8. a

The particula r embodiment of my invention illustrated in these drawings comprises an elongated hood structure supported from a cantilever-type top bracket and provided with a light transmitting globe formed of two comr 2 plementary parts. These globe parts are joined at their. open ends by a clamp whichjalso serves to attach the globe structure .as a whole to the center portions of two guidev rails formingpart of a globe-supporting frame which is hinged at one end and latched at its other endto the hood structure. The hood and the globe-supporting frame therein are formed of metal having the same or substantially the .same temperature coeflicient of expansion and contraction and the globe, by reason of its central support on its supporting frame, is free to move lengthwise thereof to accommodate its different rate of thermal expansion and contraction. The globe in its closedrposition encloses the reflectors and the supports at the ends thereof for'a plurality of elongated light sources which in the arrangement shown are tubular fluorescent lights. ;A more detailed disclosure of the luminaire will now be given in the following descrip-. tion thereof.

The mechanical design of the luminaire is such that it is supported from one cantilever-type top bracket in order toeliminate all externally positioned guides and supports'there'for. The hood 1 which constitutes part of the body structure of the luminaire is hung from a channel'shapedbracket 2' having a mounting portion extending beyond. the inner end of the hood and a ta-" pered portion of decreasing thickness extending along the top 'of the hood and'having flanged edges which are attached, thereto forming a hollow enclosure in the bracket. Asshown in Fig. 2, the dome is provided with wiring passages 3 -which extend therethrough into the enclosureof the'bracket'. The mounting portion of the ber such as, the pole 8 there illustrated.

attached to a clamp 7 which in the arrangement illus-' trated in Fig. 1 comprises two clamping members which are connected' by bolts which when tightened produce a secure clamping engagement with a supporting mom apparent that other members may be substituted for the clamp '7s0 that the luminaire may be supported on the sidewalls'of buildings or on supporting means other than the pole-type support illustrated in Fig. l.

The hood 1 ofthe luminaire is reinforced bytrans verse braces "9 and 10 which are fastened to the down turned edges of the hood and also to the top of the reflectors therein in such a way that the whole structure becomes a boxed member providing the'grea'test rigidity possible for the weight and shapes involved. The ballast units, filament transformers, and capacitors connected in the lamp circuits are mounted within the hood on these transverse braces 9 and 10' or directly on the inside surface of the hood. The mounting of the filament a transformer 11 on'the brace 9 has been illustrated in'. the drawing, but the other parts referred to as well as the wiring has not been illustrated in order to simplify the drawing. It is of course understood that the input wires to these devices in the hood will extend through the wiring passageways 3 into the interior of bracket 2.

flectors are provided with stiffening ribs"'14 which arethe hood near its point of I attachment therewith to form;

Two reflectors 12 and '13, which are mounted back-- to-back and are pointed along the street in opposite di rections, constitute the reflector structure of the luminaire which is mounted in the hood ll thereof. These reflattened along an area where thereflectors engage one another along their back surfaces. tend lengthwise of the hood and each has one longitudinal edge portion attached to the hood andflanged within seatstor the wall stiiietilie about the opening in 'tii' It is of course These reflectors ex-,

elongated globe 15 of the luminaire. The other longi' tudinal edge portions of these reflectors 12 and 13. are bent inward toward one another and fastened to one another to provide an assembly which positions the refiectors 12 and 13 relative to one another and the hood structure 1 of the luminaire.

Two members 16 and 17, each constituting end fillers and lamp socket supports are mountediin hood 1 at thel ends of reflectors 12' and 13 so that one surfacethereof forms a continuation across the ends of the reflectors of the globe. seats provided by their flanged edge 'portions' above referred to. Gasket strips of suitable material, such as neoprene sponge, are attached to these globe seats for forming a rain and dust tight connection betweenthe globe'and'the body structure'of the luminaire. These gasket strips may be attached to'the globe seats by a suitable adhesive cement. V 19. of these members 16 and 17extenddownwardly from the hood to position lampsockets 20 and 21 at the ends as reflectors 12 and 13. Pairs of fluorescent lights 22 and 23Jare mounted in a horiz ontal plane'between alignedsockets 20 and 21 and constitute the two light sources ofi the luminaire which arerespectivel y positioned-in'front ofeach of its reflectors 12 and 13.

Globe 15 of the luminaire is preferably transparent and made of a clear molded plastiomaterial. For convenience in manufacture it is made in two pieces which Whenjoined along their inner open ends form the completed globe. The two parts may be made of equal size and in the same mold thereby reducing the cost of manufacture. As best shown in Figs; 4, and 6, prisms 38 are provided on the inside end surfaces of the globe and prisms 39 are provided on the outside bottom portion thereof. As shown in Fig. 8 these prisms are-symmetrical and have facing surfaceswith an angularity of 20. Theseprisms are provided for their obscuring efiect at the ends and bottom of theglobe, but may be faced to secure a desired distribution of light. They also serve to efiect an elongation of the light source as viewed from the street and to prevent a dark area along the bottom of the luminaire where the reflector thereof blocks a direct supply of light from the lamps therein. i

As shown in Figs. 2, 3 and'4, accordingfto the invention claimed herein globe 15 is attached to'and. supported by .a globe frame having spaced side members 40 and spaced cross members 41 making a freelysliding connection with said side members for lengthwise movement thereof. Each cross member 41 is formed oftwo parts attached to the outer top edges of -the globe and each of these parts is provided with a'slot that fits over a reduced portion of the ends of the side rails near the ends thereof. These cross members in combination with a strip joining their inner ends and a strip located inside the globe and between which the upper end portions. of the globe are sandwiched in a bolted assembly, serve to reinforce the top edge portion of the globe at its ends.

The ends of the side rails 40 at .the'outer end portion.

member '42 having a body portion 43 which is attached. to the flanged outer end of the hood and has. turned over,

portions,.44i at each end thereof which are adapted to receive the inturned ends of the side rails 40 to complete the hinged connection. The turned. over end portions 44 of 'the'hinge member 42 has'open'portions at the top outer. ends thereof through which the inturned ends of the side rails '40 may freely pass, and closed inner. por tions which receive and hold the slotted end portions 45 fotming'pa rt of a catch or latch 4'6 which is assembled at portion 45 of latch 46 is located within theclosed porn ns'oii parts 44 of hinge'mernber 42. Consequently,

The lamp socket-supports 18 and As best shown. in Figs. 8 and 9,

.4 portions 44 of hinge member 42 and can be moved from positions in.which its end portions either close or open the passageway in the outer ends of the hinge member for the inturned ends of side rails 40. When latch 46 is turned into a position uncovering the end portions of parts 44 of hinge member 43, the inturned ends of the side rails 40 may be removed from hinge member 42 in order to remove the globe frame and the globe supported thereby from its hinged support in hood 1 of the luminaire.

The ends of side rails 40' at the inner end of the luminaire are turned inwardly toward one another and ted wi h. 9 9. ano her b a member 47 forming P of a latch whose other part 48 is pivoted on a hinge pin 49 which extends transversely ofand is supported by the side walls of the top bracket 2 of the luminaire. Part 48 of the latch is biased toward the other part 47 thereof by aspring 50 nd member 48 is provided with a cammed striking face 51 which engages part 47 f 'l'h latcliwhen the globe frame is moved toward the hood to its closed. position. Inthe closed position, member. 47, ofthe. latch, which is mopnted fan? the "grids off the, globe name," engages and isjh eld in; aslotted pontion of part 48 of the latch i1; order to complete the utter ng connection which holds the'frainein its' closed portioni With this arrangemeot the globe and the'franie in whichfit is supported maybe pushed 'i n to plfa'ce withouthandling the latch since the latch ma nstr am: goes into the engaged position.

The'complementary parts, 52 and53 of globe 15- are provided," along; their upper edges which form the openiug in the'coriipleted globe, with flangededge portions which re reet d to accommodatefthe side rails'40 and end 'members41 offthe globe name, The open endsj'of parts 52ian d 53 aref'a'ssembled and held in place relatiyeIto one; enothenbet'ween two, clamping straps 5.4 and fi'iw ic 'si s he an s. edgesf offparts 52' and s3 to'pr o'vide, a rigid globeassenibly at the clamp. The ends of the clamping 'st rfaps54and 55 are alsofattached to a mid-"portion efs'ide rails 40' in order to complete a conneetiori'hetween the globe and i ts supporting frame. At uieesd corners of the globe, members 40'and 41 of the globe frame are provided with cutaway portions which prey ent interference between these members the flanged edgesfof the globe. By reasonoffthecons truction mp d. the e g s. f h g obe und e v n e as p o e e n rce me a pi es; which permitjthe endsfof the globe,fon each'sigie of clamp by which it is s upop cprtedv on s ideirails lll to move freely lengthwise of these side rails t'oaccommodate the unequalexpansion'and. contractionrof the globe, which is formedof plastic, and the siderails', which are formed of metal. The g'lobe-supporting' frame and hood 'in which it' is mounted are both formed of. metal and will have corresponding amounts of thermal contraction and exp -lasagna the consequent correspondence in thefchan'ge f theseparts will not'i terrere wnh' the hinged n of the globe frame inthe hood 1 of the lumifeet, the dilference in expansion between an aluminum hood and a plastic globe willamount to about /a of an' inch in the usual range of outdoor temperatures. The particular 'luminaire being described is designed for accommodating four 6 ft. fluorescent lamps of the rapid start street lighting type, each of which is rated at 53 OOlumens.

It is quite obvious that the particular embodiment of to cover inthe appended claims all such modifications fall withinthe true spirit andscope of my invention. What I clairnfas new and desire to secure by Letters Patent er th'eTUnit ed States isz' "l. luminaire comprising; an elongatedhood having For a luminaire "having an' o verall length of 7' an elongated opening therein for a globe; an elongated globe-supporting frame including a pair of spaced side rails mounted in and extending lengthwise of said globe opening in said hood; an elongated globe formed of a light-transmissive material having a temperature coeflicient of expansion differing from that of said frame, said globe having a pair of lengthwise extending sidewalls and a pair of end walls closing the respective ends of said side walls forming an elongated opening extending lengthwise of said globe, and a supporting flange extending along the sidewalls adjacent thatportion thereof which forms a part of said globe opening with the flanged portions of said globe engaged by said side rails; and clamps mounted on the closed ends of said globe, said clamps having end portions supported on the end portions of said side rails with which they make a freely sliding connection for movement lengthwise thereof as a result of differential expansion and contraction between said globe and said globe-supporting frame under varying temperature conditions.

2. A luminaire comprising: an elongated hood having a seating surface therein for the wall structure of a globe at an elongated opening therein; an elongated globe formed of a light transmitting material and having a pair of side walls joined at the ends forming an elongated opening extending lengthwise of said globe and a supporting flange on each side wall adjacent said globe opening forming a portion thereof; means holding the wall structure of said globe at the opening therein against said seating surface in said hood including a frame having spaced side members formed of a material having a temperature coefficient of expansion differing from that of said globe and spaced cross members making a freely sliding connection with said side members for lengthwise movement thereof, said side members engaging said globe flanges and supporting said globe thereby; and means attaching said cross members of said globe holding means to the closed ends of said globe.

said side walls, and flanged surfaces extending lengthwise of each of said side walls; and means supporting said globe in said luminaire comprising an elongated globesupporting frame including a pair of spaced side rails formed of a material having a temperature coefficient of expansion differing from that of said globe and supporting said side walls by said flanged surfaces, and cross members mounted on said end walls of said globe having end portions supported on the end portions of said side rails, the flanged surfaces of said globe, and the end portions of said cross members engaging said side rails with a freely sliding connection for movement lengthwise thereof due to differential dimensional changes of said globe and side rails under varying temperature conditions.

References Cited in the file of this patent UNITED STATES PATENTS 1,738,383 Millar Dec. 3, 1929 2,259,152 Claspy Oct. 14, 1941 2,269,182 Claspy et al Jan. 6, 1942 2,337,833 Pahl Dec. 28, 1943 2,465,141 Wakefield Mar. 22, 1949 2,490,191 Baker Dec. 6, 1949 2,529,122 Zelov Nov. 7, 1950 FOREIGN PATENTS 530,492 Great Britain 1940 169,760 Austria 1951 OTHER REFERENCES Chemical Engineers Handbook, 2nd edition, pages 480-484. 

